Lucy is the women that helps Desmond in the first three games. She claims that she don't like Abstergo and in AC2 she comes to help Desmond get out. Then you meet her friends that are the Assassins. Then when Desmond trusts her most he kills her because the apple made him. For the next two ACs player wonder why the apple made Desmond do that. But then In AC3 Desmond says that Lucy was going to take the apple back to Abstergo and he choise to kill her. But one thing I thought of was when he told Lucys friends, wouldn't they be mad? Or even think that's not true because they were best friends with lucy? And why wouldn't they be in on it to? Never the less the friends where dedicated on stoping Abtergo and saving the world. If Abstergo got that apple the game might of ended right there. So thank goodness for Desmond.